I Observing a Collapsing Shell: Time Dilation Explained

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Observers inside a collapsing shell approaching a black hole's Schwarzschild radius would experience significant time dilation effects. As the shell contracts, the observer's clock would appear to run slower compared to a distant clock, while the external universe would seem to speed up. Once the shell passes the Schwarzschild radius, the observer becomes unable to detect local changes, as the event horizon expands outward at light speed. The discussion emphasizes that the observer can still move freely until the shell reaches them, despite the unusual scenario of being inside a black hole. Ultimately, the experience of time and observation is profoundly altered by the gravitational effects of the collapsing shell.
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Observer inside collapsing shell problem.
What does and observer inside of a collapsing shell observe? Lets say we have a shell of matter collapsing to a black hole. What would observers near the center see? How would the rest of the universe appear when,

The shell is approaching the Schwarzschild radius?

After the shell passes the Schwarzschild radius?

Time Dilation inside a hollow shell According to here you get time dialation, so what happens as the shell contracts?

Say the observer has a clock, and the inside of the shell is like a mirror, theres a clock attached to the shell and finally there's a clock at a great distance. How fast would these clocks go relative to eachother?

Until the shell reaches the observer, the observer is free to move aorund, so the issue to me seems to be that whe have a shell observer inside of a black hole, which normally you're not supposed to be able to have.
 
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See https://www.physicsforums.com/threa...of-a-singularity-before-it-is-formed.1017274/. A lot of your question is answered by that. Basically, the event horizon forms inside the shell and expands outward at the speed of light. Once it passes you (you can't detect anything locally as it does) you're doomed. You just don't see any local curvature until the shell passes you in the other direction.
 
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Thread 'Physical Interpretation of Frame Field'

Moderator's note: Spin-off from another thread due to topic change. In the second link referenced, there is a claim about a physical interpretation of frame field. Consider a family of observers whose worldlines fill a region of spacetime. Each of them carries a clock and a set of mutually orthogonal rulers. Each observer points in the (timelike) direction defined by its worldline's tangent at any given event along it. What about the rulers each of them carries ? My interpretation: each...
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